BACKGROUND This in vitro experimental study investigated and compared the physical properties of three newly developed atraumatic restorative treatment materials. MATERIALS AND METHODS Atraumatic Restorative Treatment materials (ART) with three different compositions were prepared by varying the percentage of Azadirachta indica (Neem) extract within the materials. Micro-hardness, compressive strength, marginal adaptation to tooth structure of the atraumatic restorative treatment materials were assessed. Statistical Analysis Used- Data was analysed using SPSS version 20 statistical software. One-Way ANOVA, Tukey's Highly Significant Difference (HSD), Scheffe's tests were conducted to assess the level of significance of differences between mean values in post-hoc testings. P RESULTS The micro-hardness of ART-I was found to be 21.1-25.8 VHN, whilst ART-II showed values between 13.2-16.3 VHN. The compressive strengths of ART-I and II were 38.2-56 and 43.3-61 MPa respectively. The micro-hardness of the ART-III was from 35.3-36.4 VHN. However, the compressive strength of ART-III was 31.2-38 MPa. Micro-hardness was recorded as significantly high when compared between the groups (P 0.05), the compressive strength of ART-III was significantly greater than those of the ART-I and II (P CONCLUSION The ART-II product evaluated physical properties consistent with promising Atraumatic Restorative Treatment materials, unlike the ART-I and III. KEY WORDS Antibacterial Agent, ART Materials, Compressive Strength, Marginal Adaptation, Marginal Gap, Micro-Hardness, Neem.